Prioritized query

ABSTRACT

According to some of the preferred embodiments, a solution framework is employed that includes defining of a mechanism to run multiple queries in a single message exchange along with a priority on a per-query basis, In some embodiments, a system for facilitating handover of a mobile device across heterogeneous access networks by ensuring response to queries transmitted by the mobile device includes: a) a mobile device having a plurality of wireless network interfaces for communicating over a plurality of heterogeneous access networks, having a media independent handover (MIH) entity to facilitate handovers between the heterogeneous networks, and configured to transmit queries related to handover operation between the heterogeneous access networks to MIH entities within said heterogeneous access networks; and b) said media independent handover entity of said mobile device being configured to transmit multiple queries in a single message exchange to an MIH entity in an access network with prioritization among said multiple queries.

CLAIM FOR PRIORITY

The present application claims priority tinder 35 U.S.C. 119 to priorprovisional application Ser. No. 60/886,158, filed Jan. 23, 2007,entitled Prioritized Query, to Y. Oba, et al., the entire disclosure ofwhich is incorporated herein by reference.

BACKGROUND Background Applications (No Priority Claimed)

The entire disclosures of each of the following U.S. Non-Provisional andU.S. Provisional Patent Applications are incorporated herein byreference: Ser. No. 11/267,590, filed on Nov. 7, 2005, entitled NetworkDiscovery Mechanisms; and Ser. No. 10/761,243 entitled MobilityArchitecture Using Pre-Authentication, Pre-Configuration and/or VirtualSoft-Handoff, filed on Jan. 22, 2004.

Field of the Invention

The present application relates to wireless networking and, in somepreferred embodiments, to systems and methods for overcoming queryingissues in wireless networks and/or the like.

General Background Discussion

Networks and Internet Protocol:

There are many types of computer networks, with the Internet having themost notoriety. The Internet is a worldwide network of computernetworks. Today, the Internet is a public and self-sustaining networkthat is available to many millions of users. The Internet uses a set ofcommunication protocols called TCP/IP (i.e., Transmission ControlProtocol/Internet Protocol) to connect hosts. The Internet has acommunications infrastructure known as the Internet backbone. Access tothe Internet backbone is largely controlled by Internet ServiceProviders (ISPs) that resell access to corporations and individuals.

With respect to IP (Internet Protocol), this is a protocol by which datacan be sent from one device (e.g., a phone, a PDA [Personal DigitalAssistant], a computer, etc.) to another device on a network. There area variety of versions of IP today, including, e.g., IPv4, IPv6, etc.Each host device on the network has at least one IP address that is itsown unique identifier.

IP is a connectionless protocol. The connection between end pointsduring a communication is not continuous. When a user sends or receivesdata or messages, the data or messages, are divided into componentsknown as packets. Every packet is treated as an independent unit ofdata.

In order to standardize the transmission between points over theinternet or the like networks, an OSI (Open Systems Interconnection)model was established. The OSI model separates the communicationsprocesses between two points in a network into seven stacked layers,with each layer adding its own set of functions. Each device handles amessage so that there is a downward flow through each layer at a sendingend point and an upward flow through the layers at a receiving endpoint. The programming and/or hardware that provides the seven layers offunction is typically a combination of device operating systems,application software, TCP/IP and/or other transport and networkprotocols, and other software and hardware.

Typically, the top four layers are used when a message passes from or toa user and the bottom three layers are used when a message passesthrough a device (e.g., an IP host device). An IP host is any device onthe network that is capable of transmitting and receiving IP packets,such as a server, a router or a workstation. Messages destined for someother host are not passed up to the upper layers but are forwarded tothe other host. In the OSI and other similar models, IP is in Layer-3,the network layer.

Wireless Networks:

Wireless networks can incorporate a variety of types of mobile devices,such as, e.g., cellular and wireless telephones, PCs (personalcomputers), laptop computers, wearable computers, cordless phones,pagers, headsets, printers, PDAs, etc. For example, mobile devices mayinclude digital systems to secure fast wireless transmissions of voiceand/or data. Typical mobile devices include some or all of the followingcomponents; a transceiver (i.e., a transmitter and a receiver,including, e.g., a single chip transceiver with an integratedtransmitter, receiver and, if desired, other functions); an antenna, aprocessor; one or more audio transducers (for example, a speaker or amicrophone as in devices for audio communications), electromagnetic datastorage (such as, e.g., ROM, RAM, digital data storage, etc., such as indevices where data processing is provided); memory; flash memory; a fullchip set or integrated circuit; interfaces (such as, e.g., USB, CODEC,UART, PCM, etc.); and/or the like.

Wireless LANs (WLANs) in which a mobile user can connect to a local areanetwork (LAN) through a wireless connection may be employed for wirelesscommunications. Wireless communications can include, e.g.,communications that propagate via electromagnetic waves, such as light,infrared, radio, microwave. There are a variety of WLAN standards thatcurrently exist, such as, e.g., Bluetooth, IEEE 802.11, and HomeRF.

By way of example, Bluetooth products may be used to provide linksbetween mobile computers, mobile phones, portable hand held devices,personal digital assistants (PDAs), and other mobile devices andconnectivity to the Internet. Bluetooth is a computing andtelecommunications industry specification that details how mobiledevices can easily interconnect with each other and with non-mobiledevices using a short-range wireless connection. Bluetooth creates adigital wireless protocol to address end-user problems arising from theproliferation of various mobile devices that need to keep datasynchronized and consistent from one device to another, thereby allowingequipment from different vendors to work seamlessly together. Bluetoothdevices may be named according to a common naming concept. For example,a Bluetooth device may possess a Bluetooth Device Name (BDN) or a nameassociated with a unique Bluetooth Device Address (BDA). Bluetoothdevices may also participate in an Internet Protocol (IP) network. If aBluetooth device functions on an IP network, it may be provided with anIP address and an IP (network) name. Thus, a Bluetooth Device configuredto participate on an IP network may contain, e.g., a BDN, a BDA, an IPaddress and an IP name. The term “IP name” refers to a namecorresponding to an IP address of an interface.

An IEEE standard, IEEE 802.11, specifies technologies for wireless LANsand devices. Using 802.11, wireless networking may be accomplished witheach single base station supporting several devices. In some examples,devices may come pre-equipped with wireless hardware or a user mayinstall a separate piece of hardware, such as a card, that may includean antenna. By way of example, devices used in 802.11 typically includethree notable elements, whether or not the device is an access point(AP), a mobile station (STA), a bridge, a PCMCIA card or another device:a radio transceiver; an antenna; and a MAC (Media Access Control) layerthat controls packet flow between points in a network.

In addition, Multiple interface Devices (MIDs) may be utilized in somewireless networks. MIDs may contain two independent network interfaces,such as a Bluetooth interface and an 802.11 interface, thus allowing theMID to participate on two separate networks as well as to interface withBluetooth devices. The MID may have an IP address and a common IP(network) name associated with the IP address.

Wireless network devices may include, but are not limited to Bluetoothdevices, Multiple Interface Devices (MIDs), 802.11x devices (IEEE 802.11devices including, e.g., 802.11a, 802.11b and 802.11g devices), HomeRF(Home Radio Frequency) devices, Wi-Fi (Wireless Fidelity) devices, GPRS(General Packet Radio Service) devices, 3G cellular devices, 2.5 Gcellular devices, GSM (Global System for Mobile Communications) devices,EDGE (Enhanced Data for GSM Evolution) devices, TDMA type (Time DivisionMultiple Access) devices, or CDMA type (Code Division Multiple Access)devices, including CDMA2000. Each network device may contain addressesof varying types including but not limited to an IP address, a BluetoothDevice Address, a Bluetooth Common Name, a Bluetooth IP address, aBluetooth IP Common Name, an 802.11 IP Address, an 802.11 IP commonName, or an IEEE MAC address.

Wireless networks can also involve methods and protocols found in, e.g.,Mobile IP (Internet Protocol) systems, in PCS systems, and in othermobile network systems. With respect to Mobile IP, this involves astandard communications protocol created by the Internet EngineeringTask Force (IETF). With Mobile IP, mobile device users can move acrossnetworks while maintaining their IP Address assigned once. See Requestfor Comments (RFC) 3344. NB: RFCs are formal documents of the InternetEngineering Task Force (IETF). Mobile IP enhances Internet Protocol (IP)and adds means to forward Internet traffic to mobile devices whenconnecting outside their home network. Mobile IP assigns each mobilenode a home address on its home network and a care-of-address (CoA) thatidentifies the current location of the device within a network and itssubnets. When a device is moved to a different network, it receives anew care-of address. A mobility agent on the home network can associateeach home address with its care-of address. The mobile node can send thehome agent a binding update each time it changes its care-of addressusing, e.g., Internet Control Message Protocol (ICMP).

In basic IP routing (i.e. outside mobile IP), typically, routingmechanisms rely on the assumptions that each network node always has aconstant attachment point to, e.g., the Internet and that each node's IPaddress identifies the network link it is attached to. In this document,the terminology “node” includes a connection point, which can include,e.g., a redistribution point or an end point for data transmissions, andwhich can recognize, process and/or forward communications to othernodes. For example, Internet routers can look at, e.g., an IP addressprefix or the like identifying a device's network. Then, at a networklevel, routers can look at, e.g., a set of bits identifying a particularsubnet. Then, at a subnet level, routers can look at, e.g., a set ofbits identifying a particular device. With typical mobile IPcommunications, if a user disconnects a mobile device from, e.g., theInternet and tries to reconnect it at a new subnet, then the device hasto be reconfigured with a new IP address, a proper netmask and a defaultrouter. Otherwise, routing protocols would not be able to deliver thepackets properly.

I.E.E.E 802.21 Standard:

The IEEE 802.21 standard supports different handover methods. Suchmethods are generally classified as ‘hard’ or ‘soft’, depending onwhether the handover procedure is “break-before-make” or“make-before-break” with respect to the data transport facilities thatsupport the exchange of data packets between the mobile node and thenetwork. Handover decision-making involves cooperative use of bothmobile node and network infrastructure.

The IEEE 802.21 standard defines services that enhance handovers betweenheterogeneous access links.

1. A Media Independent Event Service (MIES) which provides eventclassification, event filtering and event reporting corresponding todynamic changes in link characteristics, link status, and link quality.

2. A Media Independent Command Service (MICS) which enables MIH Users tomanage and control link behavior relevant to handovers and mobility.

3. A Media Independent Information Service (MIIS) which provides detailson the characteristics and services provided by the serving andneighboring networks. The information enables effective system accessand effective handover decisions.

An MIHF provides asynchronous and synchronous services throughwell-defined Service Access Points (SAPs) for link layers and MIH Users.(MIHF is a logical entity that facilitates handover decision making. MIHUsers make handover decisions based on inputs from the MIHF.) In thecase of a system with multiple network interfaces of arbitrary type, theMIH Users may use the Event Service, Command Service and InformationService provided by MIHF to manage, determine, and control the state ofthe underlying interfaces.

These services provided by MIHF help the MIH Users in maintainingservice continuity, service adaptation to varying quality of service,battery life conservation, network discovery, and link selection. In asystem containing heterogeneous network interfaces of IEEE 802 types andcellular (3GPP, 3GPP2) types, the MIHF may help the MIH Users toimplement effective procedures to couple services across heterogeneousnetwork interfaces. MIH Users may utilize services provided by the MIHFacross different entities to query resources required for a handoveroperation between heterogeneous networks.

MIH services in mobile nodes facilitate seamless handovers betweenheterogeneous networks. An MIH User such as a mobility managementprotocol (e.g., Mobile IP) could be supported for handover and seamlesssession continuity. This shall not preclude other protocols in additionto Mobile IP and even other MIH Users from making use of MIH services tooptimize handovers.

An illustrative network model including MIH services is shown in FIG. 1to better illustrate the MIH Communication Reference Points. Moving fromright to left, the model includes an MIH-capable mobile node (MN, farright) that supports multiple wired and wireless access technologies.The model assumes that the serving network either operates multiplelink-layer technologies or allows its user to roam into other networkswhen a service level agreement (SLA) in support of inter-working hasbeen established. The model illustrates access networks that areconnected in some loose, serial way to a given core network. (i.e., CoreOperator 1, 2, or 3).

Also depicted is an access network that is more tightly coupled (AccessNetwork-3). Each Core Operator network (1, 2, or 3) might represent aservice provider, corporate intranet provider, or just another part ofthe visited or home access. In this depicted model the provisioningprovider is operating Access Network-3, which couples the terminal tothe core (labeled Home Core Network) via R1.

At any given point in time, the subscriber's serving network may be thehome network or a visited network. The network providers offer MIHservices in their access networks (Access Network-1 to 4) in order tofacilitate heterogeneous handovers into their networks. Each accesstechnology either advertises its MIH capability or responds to MIHservice discovery. Each service provider for these access networksallows access to one or more MIH Points of Service (PoS) node(s). ThesePoS nodes may provide some or all of the MIH services as determinedduring the MIH capabilities discovery. The PoS location may vary basedon the operator deployment scenario and the technology-specific MIHarchitecture.

An MIH PoS may reside next to, or co-located with, the point ofattachment (PoA) node in the access network (e.g., Access Network 1, 2,4). Alternatively, the PoS may reside deeper inside the access or corenetworks (e.g., Access Network 3). As shown in FIG. 3, the MIH entity inthe MN can communicate with MIH network entities using reference pointsR1, R2, or R3 over any of the available access network. If the PoA inthe serving access network has a co-located MIHF, the R1 referenceconnection terminates at the PoA which is also the PoS (MN to AccessNetwork 1, 2, 4 of the model can all be R1). In that case an R3reference connection would be terminated at any non-PoA (illustrated byMN connectivity to Access Networks 1, 2, 4). MIH events may originate atboth sides of an active R1 link. The MN is typically the first node toreact to these events.

The interaction of visited and home networks could be either for controland management purposes or for data transport purposes. It is alsopossible that due to roaming or SLA agreements, the home network mayallow the MN to access the public Internet directly through a visitednetwork. As illustrated, two MIH network entities may communicate witheach other via R4 or R5 reference points. The MIH capable PoA may alsocommunicate with other MIH network entities via R4 and R5 referencepoints. The MIH capable MN could have an MIH communication with otherPoA in the candidate access networks via R2 reference point to obtaininformation Services about the candidate network.

With regard to the MIH Information Service, visited providers can offeraccess to their information server located in an MIH PoS node (upper farleft). The operator provides the MIIS to mobile nodes so they can obtainpertinent information including, but not limited, to new roaming lists,costs, provider identification information, provider services,priorities and any other information that would enable the selection andutilization of these services. As illustrated, it is possible for themobile node to be pre-provisioned with MIIS data by its provider. Alsopossible is for the mobile node to obtain MIH Information Services fromany access network of its provider or visited networks that maintain SLAagreements with the provisioner. MIIS could also be available fromanother overlapping or nearby visited network, using that network's MIISpoint of service. The serving network may utilize R4 and R5 interfacesto access other MIH entities. As an example, in FIG. 3 the home networkmay access its own MIH information server or core operator 1 (visitednetwork) MIH information server.

The IEEE 802.21 standard supports the Media independent Event service,Media Independent Command service and Media Independent Informationservice. The MIH Protocol defines the format of the messages (i.e. MIHFpacket with header and payload) that are exchanged between remote MIHFentities and the transport mechanisms that support the delivery of themessages. The selection of the transport mechanism is dependent on theaccess technology that connects the MN to the network and the locationof the MIH PoS.

The packet payload for these services may be carried over L2 managementframes, L2 data frames or other higher layer protocols. Wirelessnetworks such as 802.11 and 802.16 have a management plane and supportmanagement frames which could be suitably enhanced for carrying theabove payloads. However, the wired Ethernet network does not havemanagement plane and may carry the above payloads only in data frames.

The IEEE 802.21 standard defines the packet format and payloads in mediaindependent manner in standard TLV (Time-Length-Value) format. See,e.g., FIG. 5(C) illustrating standard TLV format. Thereafter, thesepackets may be encapsulated in a L2 MIH Protocol using MIHF Ethertypewhen the payload needs to be sent over normal data frames as in case ofEthernet. In other cases the TLV based messages and payload may bedirectly encapsulated in media specific management frames.Alternatively, MIH protocol messages may be encapsulated using a lowerlayer (L2) or a higher layer (L3 and above) transport.

The IEEE 802.21 standard defines the format of MIH Protocol data unit(PDU) header and payload. Standard TLV format provides media-independentrepresentation for the PDU payload contents. The MIHF PDUs areencapsulated in data frames with MIHF Ethertype over 802 links. For802.11 and 802.16 links extensions of media-specific management framesare recommended for carrying MIH messages. No assumptions are made inthis standard regarding the transport of MIH messages over 3SGPP and3GPP2 access links at L2.

MIHF Transactions and Messages:

An MIHF transaction involves combination of an MIHF Request orIndication message and the corresponding MIHF Response message (ifapplicable) that are exchanged between two MIHF peers. It is required tomatch each request message that is sent by the initiator with itsresponse message. Acknowledgement messages associated with this messageexchange are also part of the transaction.

In MIH protocol messages, all TLV definitions are always aligned on anoctet boundary and hence no padding is required. FIG. 5(A) shows thecomponents of the MIH protocol frame. With reference to FIG. 5(B), theMIH protocol header carries the essential information which is presentin every frame and is important for parsing and analyzing the MIHprotocol frame.

The following TLV encoding can be used for parameters in MIH ProtocolMessages. The Type field is one octet. The format of the Length fieldshall be per the “definite form” of ITU-T X.690. Specifically, if theactual length of the Value field is less than or equal to 127 octets,then a) the length of the Length field shall be one octet, b) the MSB ofthe Length field shall be set to 0, and c) the other 7 bits of theLength field shall be used to indicate the actual value of the Valuefield in octets.

If the length of the Value field is more than 127 octets, then: a) thelength of the Length field shall be one octet more than what is actuallyused to indicate the length of the Value field in octets; b) the MSB ofthe first octet of the length field shall be set to 1; c) the other 7bits of the first octet of the length field shall be used to indicatethe number of additional octets of the Length field (i.e., excluding thefirst octet); and d) the remaining octets (i.e., excluding the firstoctet) of the Length field shall be used to indicate the actual lengthof the Value field. TLV type values shall be unique. TLV encoding startat 1 and subsequent values are assigned in ascending order.

All MIH messages carry a source MIHF ID followed by a destination MIHFID as the first two TLVs of the MIH protocol payload part of themessage. By way of example, an MIH_Get_Information request message isused by an MIHF to retrieve a set of Information Elements provided bythe information service. A single MIH_Get_Information request messagecan carry multiple queries of a combination of Binary, RDF_Data,RDF_Schema_URL and RDF_Schema types. An illustrative MIH_Get_Informationmessage format is shown in FIG. 5(D).

Illustrative Computer Architectures:

FIG. 2 depicts some illustrative architectural components that can beemployed in some illustrative and non-limiting implementations includingwireless access points to which client devices communicate. In thisregard, FIG. 2 shows an illustrative wireline network 20 connected to awireless local area network (WLAN) generally designated 21. The WLAN 21includes an access point (AP) 22 and a number of user stations 23, 24.For example, the wireline network 20 can include the Internet or acorporate data processing network. For example, the access point 22 canbe a wireless router, and the user stations 23, 24 can be, e.g.,portable computers, personal desktop computers, PDAs, portablevoice-over-IP telephones and/or other devices. The access point 22 has anetwork interface 25 linked to the wireline network 21, and a wirelesstransceiver in communication with the user stations 23, 24. For example,the wireless transceiver 26 can include an antenna 27 for radio ormicrowave frequency communication with the user stations 23, 25. Theaccess point 22 also has a processor 28, a program memory 29, and arandom access memory 31. The user station 23 has a wireless transceiver35 including an antenna 36 for communication with the access pointstation 22. In a similar fashion, the user station 24 has a wirelesstransceiver 38 and an antenna 39 for communication to the access point22. By way of example, in some embodiments an authenticator could beemployed within such an access point (AP) and/or a supplicant or peercould be employed within a mobile node or user station.

FIG. 3 shows an illustrative computer or control unit that can be usedto implement computerized process steps, to be carried out by devices,such as, e.g., an access point, a user station, a mobile node or othernode in some embodiments. In some embodiments, the computer or controlunit includes a central processing unit (CPU) 322, which can communicatewith a set of input/output (I/O) device(s) 324 over a bus 326. The I/Odevices 324 can include, for example, a keyboard, monitor, and/or otherdevices. The CPU 322 can communicate with a computer readable medium(e.g., conventional volatile or non-volatile data storage devices) 328(hereafter “memory 328”) over the bus 326. The interaction between a CPU322, I/O devices 324, a bus 326, and a memory 328 can be like that knownin the art. Memory 328 can include, e.g., data 330. The memory 328 canalso store software 338. The software 338 can include a number ofmodules 340 for implementing the steps of processes. Conventionalprogramming techniques may be used to implement these modules. Memory328 can also store the above and/or other data file(s). In someembodiments, the various methods described herein may be implemented viaa computer program product for use with a computer system. Thisimplementation may, for example, include a series of computerinstructions fixed on a computer readable medium (e.g., a diskette, aCD-ROM, ROM or the like) or transmittable to a computer system via andinterface device, such as a modem or the like. A communication mediummay be substantially tangible (e.g., communication lines) and/orsubstantially intangible (e.g., wireless media using microwave, light,infrared, etc.). The computer instructions can be written in variousprogramming languages and/or can be stored in memory device(s), such assemiconductor devices (e.g., chips or circuits), magnetic devices,optical devices and/or other memory devices. In the various embodiments,the transmission may use any appropriate communications technology.

While a variety of systems and methods are known, there remains a needfor improved systems and methods, including, e.g., systems and methodsfor improving the ability to gain network access.

SUMMARY

The present invention overcomes various limitations and deficiencies inthe background art.

According to some of the preferred embodiments, a solution framework isemployed that includes defining of a mechanism to run multiple queriesin a single message exchange. In some preferred examples, multiple queryrequests are contained in a single request message and multiple queryresponses for the multiple query requests are contained in a singleresponse message. In I.E.E.E. 802.21 Information Service, this mechanismis already defined, but without any prioritizing among multiple queries.

According to some of the preferred embodiments, the solution frameworkdefines priority on a per-query basis. In some of the preferredembodiments, there are two potential approaches.

According to a first approach, each query request is tagged with apriority value (e.g., explicit prioritization).

According to a second approach, the query requests in a request messageare ordered based on priority (e.g., implicit prioritization). Forexample, higher priority query requests can be followed by lowerpriority ones in the request message. In this regard, the queryresponses for higher priority query requests will have a greater chanceto be included in a response message than that for lower priority ones,when the maximum response size does not afford to include all of them.

According to some embodiments, a system for facilitating handover of amobile device across heterogeneous access networks by ensuring responseto queries transmitted by the mobile device includes: a) a mobile devicehaving a plurality of wireless network interfaces for communicating overa plurality of heterogeneous access networks, having a media independenthandover (MIH) entity to facilitate handover between the heterogeneousnetworks, and configured to transmit queries related to handoveroperation between the heterogeneous access networks to MIH entitieswithin the heterogeneous access networks; and b) the media independenthandover entity of the mobile device being configured to transmitmultiple queries in a single message exchange to an MIH entity in anaccess network with prioritization among the multiple queries.

According to some embodiments, a method for facilitating handover of amobile device across heterogeneous access networks by ensuring responseto queries transmitted by the mobile device, comprising: a) providing amobile device having a plurality of vireless network interfaces forcommunicating over a plurality of heterogeneous access networks, havinga media independent handover (MIH) entity to facilitate handoversbetween the heterogeneous networks, and configured to transmit queriesrelated to handover operation between the heterogeneous access networksto MIH entities within the heterogeneous access networks; and b) themobile device transmitting multiple queries in a single message exchangeto an MIH entity in an access network with prioritization among themultiple queries.

In some examples, the mobile device is configured to tag at least someof the multiple queries with a priority value. In some examples, thetags are included in at least one TLV within the message. In someexamples, the tags are included in a reserved octet of a TLV value fieldof the at least one TLV. In some examples, the tags are included in afirst octet of a TLV value field to indicate a pority. In some examples,the mobile device is configured such that queries in a request messageare ordered based on priority. In some examples, the mobile device isconfigured to arrange at least some higher priority queries in advanceof lower priority queries, such that the query responses for such higherpriority query requests will have a greater chance to be included in aresponse message. In some examples, the MIH entity in the mobile deviceand the MIH entity in the access network are configured to employ IEEE802.21 protocols.

The preferred embodiments of the invention can achieve the followingand/or other advantages:

First, a querier (e.g., which makes the query) can obtain as muchinformation as possible within a given response size limit.

Second, existing query languages do not have to be changed (e.g.,existing query languages can be employed without changing).

The above and/or other aspects, features and/or advantages of variousembodiments will be further appreciated in view of the followingdescription in conjunction with the accompanying figures. Variousembodiments can include and/or exclude different aspects, featuresand/or advantages where applicable. In addition, various embodiments cancombine one or more aspect or feature of other embodiments whereapplicable. The descriptions of aspects, features and/or advantages ofparticular embodiments should not be construed as limiting otherembodiments or the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred embodiments of the present invention are described by wayof example in reference to the accompanying drawings, in which:

FIG. 1 is an illustrative network model from the IEEE 802.21 Standardfor reference;

FIG. 2 depicts some illustrative architectural components that can beemployed in some illustrative and non-limiting implementations includingwireless access points to which client devices communicate;

FIG. 3 shows an illustrative computer or control unit that can be usedto implement computerized process steps, to be claimed out by devices,such as, e.g., an access point, a user station, a mobile node or othernode in some embodiments;

FIG. 4 is a diagram showing illustrative communications between a mobilenode (MN) and other network entities;

FIG. 5(A) is a diagram showing an illustrative MIH protocol generalframe format from the IEEE 802.21 Standard;

FIG. 5(B) is a diagram showing an illustrative MIH protocol headerformat from the IEEE 802.21 Standard;

FIG. 5(C) is a diagram showing an illustrative TLV format; and

FIG. 5(D) is a diagram showing an illustrative message from the IEEE802.21 Standard.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the present invention may be embodied in many different forms, anumber of illustrative embodiments are described with the understandingthat the present disclosure is to be considered as providing examples ofthe principles of the various inventions described herein and that suchexamples are not intended to limit the invention to preferredembodiments described herein and/or illustrated herein.

Existing Problems

Under 802.21, as described above, communications include, e.g., queriesand responses to such queries. For example, a mobile node (MN) cantransmit a query to, e.g., an Access Point (AP) or to an InformationServer (IS) in some examples (such as, e.g., shown in FIG. 4). However,in the existing art, there are some cases in which a larger query can beproblematic. For example, there are some cases in which there is a limiton query response size. For example, an access network can impose limitson the size. By way of example, 802.11u employs Generic AdvertisingService (GAS) in which a size limit is imposed.

In this regard, if the size of the generated response is larger than themaximum response size, then the entire query with fail. Moreover,despite such a failure, the query would consume a certain amount ofnetwork resources.

The Preferred Solutions

To address the above and other issues, according to some of thepreferred embodiments, a prioritized query approach is employed. In someexamples, for such an approach, less important pieces of information areremoved from the query response until the query response is of anappropriate size. For example, less important pieces of information canbe removed from the query response until the resulting response size islarger than the maximum response size (e.g., such that the resuttingquery response can be made not larger than the maximum response size).

According to some of the preferred embodiments, a solution framework isemployed that includes defining of a mechanism to run multiple queriesin a single message exchange. In some preferred examples, multiple queryrequests are contained in a single request message and/or multiple queryresponses for the multiple query requests are contained in a singleresponse message. In I.E.E.E. 802.21 information Service, a mechanismfor providing, e.g., such multiple query requests is already defined,but without providing for any prioritization among multiple queries,See, e.g., IEEE P802.21™/D04.00, Draft Standard for Local andMetropolitan Area Networks: Media Independent Handover Services,February, 2007, at 7.6.27.1.2, section Semantics of service primitive,which indicates “InfQueryType, TLV When this InfoQueryType is specified,the InfoQueryParameters shall be a binary string which encodesInformation Element TLVs that carry requests as defined in clauses6.4.6.1 and 6.4.6.2.” See also the current draft as of August, 2007,which states, e.g., “[a] single MIH_Get_Information request message cancarry multiple queries of a combination of Binary, RDF_Data,RDF_Schema_URL and RDF_Schema types.” IEEE P802.21™/D7.1, Draft Standardfor Local and Metropolitan Area Networks: Media Independent HandoverServices, August 2007, at 8.6.4.1 “MIH_Get_Information request.” Theentire disclosures of these two draft standard documents related to IEEE802.21 are incorporated herein by reference.

As indicated, the draft standard allows multiple queries in a singlerequest, but the draft standard does not contemplate anything aboutprioritization among multiple queries in a request. Prior to the presentinvention, there was no such query language that supported prioritizedquery.

According to some of the preferred embodiments, the query responses forhigher priority query requests will have a greater chance to be includedin a response message than that for lower priority ones by incorporatinga mechanism to differentiate multiple queries in a single request on apriority basis.

According to the preferred embodiments, the solution framework definespriority on a per-query basis. In some of the preferred embodiments,there are two potential approaches.

Tagged Approach

According to a first approach, each query request is tagged with apriority value (e.g., explicit prioritization).

In order to tag a priority request, preferably the message format ismodified to include such tags. In some embodiments, the tags can beachieved by, for example, reserving an octet (such as, e.g., the firstoctet) of a TLV Value field to indicate a priority. In this illustrativemanner, 255 levels of priorities could be represented. For backgroundreference (see also above discussion in background of this document), itis noted that in data communication protocols information may be encodedas a Type-Length-Value or TLV element inside of the protocol. By way ofexample, type and length fields are typically fixed in size (e.g., a fewbytes) and the value field is typically variable size. These fieldstypically used as follows: type—a numeric code which indicates the kindof field that this part of the message represents; length—the size ofthe value field (typically in bytes); and value—variable sized set ofbytes which contains data for this part of the message. Some of thegeneral advantages of using a TLV representation include TLV sequencesare easily searched using generalized parsing functions; and new messageelements which are received at an older node can be safely skipped andthe rest of the message can be parsed.

In order to employ the functionality of this Tagged Approach, the senderof the request (e.g., for example a mobile device) is preferablyconfigured (such as, e.g., with appropriate programming) to perform thefunctions of this embodiment to, e.g. a) transmit multiple queries in asingle request and b) to tag such queries according to priority. In thisregard, the priority can be assigned, e.g., based on predefined rulesand/or user input or user guidelines. In addition, the receiver of therequest can also be modified (such as, e.g., with appropriateprogramming) to a) identify queries by priority and b) to ensure thathigher priority queries are, e.g., addressed in a response message. Insome embodiments, the sender of the request can also be configured so asto separate a single query into multiple queries (e.g., based onpredefined rules), and to tag such separate queries by priority.

Ordered Approach

According to a second approach, the query requests in a request messageare ordered based on priority (e.g., implicit prioritization). Forexample, higher priority query requests can be followed by lowerpriority ones in the request message. In this regard, the queryresponses for higher priority query requests will have a greater chanceto be included in a response message than that for lower priority ones,when the maximum response size does not afford to include all of them.

In this approach, the sender of the query requests in a request message(such as, e.g., a mobile device) would have programming to modify theorder of the query requests. The sender of the multiple queries hasknowledge about which query is more important than others, and it ordersthe queries based on the knowledge. In this regard, for example, thepriority (e.g., order) can be assigned, e.g., based on predefined rulesand/or user input or guidelines. In addition, the receiver of therequest can also be configured (such as, e.g., with appropriateprogramming) to a) identify queries received in order by priority and b)to ensure that higher priority queries are, e.g., addressed in aresponse message. In some embodiments, the sender of the request canalso be configured so as to separate a single query into multiplequeries (e.g., based on predefined rules), and to send such queries in aparticular order based on by priority.

While said tagged approach and said ordered approach are employedindependently in some preferred embodiments, some embodiments could beemployed incorporating both tagged and ordered approaches (for example,such that an implicit priority could be applied based on order whilepriority could also be tagged for some queries).

While the above disclosure describes certain queries and responsesbetween illustrative entities (e.g., mobile devices and other networkentities), it should be understood based on this disclosure that aspectsof the invention can be employed in other queries and/or responsesbetween other appropriate entities, such as, e.g., between other MIHentities under 802.21.

The preferred embodiments of the invention can achieve the followingand/or other advantages:

First, a querier (e.g., which makes the query) can obtain as muchinformation as possible within a given response size limit.

Second, existing query languages do not have to be changed (e.g.,existing query languages can be employed without changing).

According to some embodiments, queries and responses can include queriesand responses as described within the above-noted pending U.S.non-provisional patent applications.

Broad Scope of the Invention

While illustrative embodiments of the invention have been describedherein, the present invention is not limited to the various preferredembodiments described herein, but includes any and all embodimentshaving equivalent elements, modifications, omissions, combinations(e.g., of aspects across various embodiments), adaptations and/oralterations as would be appreciated by those in the art based on thepresent disclosure. The limitations in the claims are to be interpretedbroadly based on the language employed in the claims and not limited toexamples described in the present specification or during theprosecution of the application, which examples are to be construed asnon-exclusive. For example, in the present disclosure, the term“preferably” is non-exclusive and means “preferably, but not limitedto.” In this disclosure and during the prosecution of this application,means-plus-function or step-plus-function limitations will only beemployed where for a specific claim limitation all of the followingconditions are present in that limitation: a) “means for” or “step for”is expressly recited; b) a corresponding function is expressly recited;and c) structure, material or acts that support that structure are notrecited. In this disclosure and during the prosecution of thisapplication, the terminology “present invention” or “invention” may beused as a reference to one or more aspect within the present disclosure.The language present invention or invention should not be improperlyinterpreted as an identification of criticality, should not beimproperly interpreted as applying across all aspects or embodiments(i.e., it should be understood that the present invention has a numberof aspects and embodiments), and should not be improperly interpreted aslimiting the scope of the application or claims. In this disclosure andduring the prosecution of this application, the terminology “embodiment”can be used to describe any aspect, feature, process or step, anycombination thereof, and/or any portion thereof, etc. In some examples,various embodiments may include overlapping features. In thisdisclosure, the following abbreviated terminology may be employed,“e.g.” which means “for example.”

1. A system for facilitating handover of a mobile device acrossheterogeneous access networks by ensuring response to queriestransmitted by the mobile device, comprising: a) a mobile device havinga plurality of wireless network interfaces for communicating over aplurality of heterogeneous access networks, having a media independenthandover (MIH) entity to facilitate handovers between the heterogeneousnetworks, and configured to transmit queries related to handoveroperation between the heterogeneous access networks to MIH entitieswithin said heterogeneous access networks; and b) said media independenthandover entity of said mobile device being configured to transmitmultiple queries in a single message exchange to an MIH entity in anaccess network with prioritization among said muttipte queries.
 2. Thesystem of claim 1, wherein said mobile device is configured to tag atleast some of said multiple queries with a priority value.
 3. The systemof claim 2, wherein said tags are included in at least one TLV withinsaid message.
 4. The system of claim 3, wherein said tags are includedin a reserved octet of a TLV value field of said at least one TLV. 5.The system of claim 4, wherein said tags are included in a first octetof a TLV value field to indicate a priority.
 6. The system of claim 1,wherein said mobile device is configured such that queries in a requestmessage are ordered based on priority.
 7. The system of claim 6, whereinsaid mobile device is configured to arrange at least some higherpriority queries in advance of lower priority queries, such that thequery responses for such higher priority query requests will have agreater chance to be included in a response message.
 8. The system ofclaim 1, wherein said MIH entity in an access network is within aninformation Server.
 9. The system of claim 1, wherein said MIH entity inan access network is within an Access Point.
 10. The system of claim 1,where said MIH entity in said mobile device and said MIH entity in saidaccess network are configured to employ IEEE 802.21 protocols.
 11. Amethod for facilitating handover of a mobile device across heterogeneousaccess networks by ensuring response to queries transmitted by themobile device, comprising: a) providing a mobile device having aplurality of wireless network interfaces for communicating over aplurality of heterogeneous access networks, having a media independenthandover (MIH) entity to facilitate handovers between the heterogeneousnetworks, and configured to transmit queries related to handoveroperation between the heterogeneous access networks to MIH entitieswithin said heterogeneous access networks; and b) said mobile devicetransmitting multiple queries in a single message exchange to an MIHentity in an access network with prioritization among said multiplequeries.
 12. The method of claim 11, further including said mobiledevice tagging at least some of said muttipte queries with a priorityvalue.
 13. The method of claim 12, further including providing said tagsin at least one TLV within said message.
 14. The method of claim 13,further including providing said tags in a reserved octet of a TLV valuefield of said at least one TLV.
 15. The method of claim 11, furtherincluding said mobile device ordering at least some of said queries insaid request message based on priority.
 16. The method of claim 15,further including arranging at least some higher priority queries inadvance of lower priority queries, such that the query responses forsuch higher priority query requests will have a greater chance to beincluded in a response message.
 17. The system of claim 11, furtherincluding said MIH entity in said mobile device and said MIH entity insaid access network employing IEEE 802.21 protocols.
 18. A system forfacilitating handover of a mobile device across heterogeneous accessnetworks by ensuring response to queries transmitted, comprising: a) amobile device having a plurality of wireless network interfaces forcommunicating over a plurality of heterogeneous access networks, havinga media independent handover (MIH) entity to facilitate handoversbetween the heterogeneous networks, and configured to transmit queriesrelated to handover operation between the heterogeneous access networksto MIH entities within said heterogeneous access networks; and b) saidmedia independent handover entity of said mobile device being configuredto transmit multiple queries in a single message exchange to an MIHentity in an access network with prioritization among said muttiptequeries.